Door latch construction



Bem-A. Qu/MQ Filed Sept. 9, 1959 B A QUINN DOOR LATCH CONSTRUCTION March 7, 1961 United States Patent() DOOR LATCH CONSTRUCTION Bert A. Quinn, zso E. sth st., st. Paul, Mimi.

Filed sept. 9, 1959, ser. No. 838,977

1 Claim. (Cl. 292-228) My invention relates generally to door latch mechanisms and more particularly to such mechanisms of the type involving a latch element mounted on a door for rotation on an axis generally normal to the plane of the door and a cooperating strike mounted on the door casing for limited movements into and out of the path of travel of the latch element and yieldingly urged toward said path of travel, said latch element being rotated out of operative engagement with the strike -to permit opening of the door.

Doors of the combination storm and screen variety, particularly those doors made from metal such as aluminum, generally comprise a framework of hollow extruded metal stiles and rails, which framework selectively supports one or more removable panes of glass and panels of metal screen mounted in subframes. In the interests of economy, the extruded members or stiles which comprise said framework are of extremely narrow width, necessitating the recessing of a strike into a door frame, that is, the frame which defines the door opening, to permit mounting of a cooperating latch on the door. Otherwise, with doors having such narrow framework members or stiles, special mounting means must be utilized to properly secure the latch to the door.

The primary object of my invention is the provision of latch mechanism comprising, a movable strike as above f set forth, and novel latch element construction, whereby the strike is not only automatically moved out of the path of travel of the latch element during-closing movements of the door, but is also moved out of the path o-f travel of the latch element by manipulation of the latch element to permit the door to be opened.

Another object of my invention is the provision of latch mechanism including a movable strike and a cooperating latch element, said latch element having, a cam surface engaging the strike to move the strike out of the path of travel of the latch element upon closing movements of the door, a latching surface engaging the strike to hold the door against opening movements, and a second strike engaging cam portion responsive to rotation of the latch element to move the strike out of said path of travel to permit opening of the door.

Still another object of my invention is the provision of latch mechanism as set forth, which can be mounted on a doorV having a stile or latch-mounting portion of minimum width, without the necessity of special mount-Y ing adapters and the like.

The above, and still further highly important objects and advantages of my invention will become apparent from the following detailed specification, appended claim and attached drawings. V

Referring to the drawings, which illustrate the invention, and in which like reference characters indicate like parts throughout the several views:

Fig. 1 is a fragmentary view partly in elevation and partly in section of a door and cooperating door casing, showing my novel latch mechanism mounted thereon,

ICC y Patented Mar. 7, 1961 taken substantially on the line 1-1 of Fig. 2, some parts i Fig. 2 is a fragmentary view partly in elevation and`V partly in section, taken substantially on the line 2-2 of Fig. 1, some parts being broken away; Y

Fig. 3 is a fragmentary horizontal section taken on the irregular line 3--3 of Fig. 2;

Fig. 4 is a vertical section taken substantially on the line 4-4 of Fig. 1;

Fig. 5 is a fragmentary section taken on the line 5-5 of Fig. 2; and

Fig. 6 is a fragmentary section taken on the line 6-6 of Fig. 4.

Referring with greater detail to the drawings, the numeral 1 indicates the stile of a conventional door 2 made from extruded metal such as aluminum, and which door is mounted by suitable hinges, not shown, for swinging movements toward and away from a conventional door casing, indicated by the numeral 3. The door casing 3 is also preferably formed from extruded metal, such as aluminum, and is formed to provide a vertically extended stop shoulder 4 in inwardly spaced relation to the louter wall 5 thereof.

A pair of mounting plates 6 and 7 lare rigidly secured t-o opposite sides of the stile 1 by means of anchoring bosses 9 and 10 extending through aligned openings 11 and 12 respectively in opposite sides of the stile 1.

The mounting plate 7 is formed to provide an outwardly extending hollow boss 13 in which is mounted an annular bearing 14 which journals theshank pontion 15 of a conventional doorknob or the like 16. The inner end of the shank 15 is formed to provide a diametrically reduced neck 17 that extends through an aperture 1S in the mounting plate 7, and which is peened or otherwise rigidly secured to an anchoring washer or the like 19 to prevent axially outward movement of the shank 1S and knob 16.

A cross sectionally polygonal Vspindle 20 extends loosely through aligned openings 21 in opposite sides of the stile 1, normal to the plane of the door 2, and is axially slidably seated at one end portion in the shank 15 of the knob 16, for common rotation therewith. v The opposite end portion of the spindle 2u is axially slidably seated in a generally cylindrical neck portion 22 of a rotary latch element, indicated in its entirety by the numeral 23. The neck portion 22 is journalled in an opening 24 in the mounting plate 6 and at its inner end 28 which loosely encompasses the neck portion 22, and

which 4has its opposite hookedA end s 29 in engagement with a stationary lug 30 integrally formed with the mounting plate 6 and a rotary lug 31 integrally formed with the latch element 23. The torsion spring 28 yieldingly urges the latch element 23 toward an intermediate latching position, indicated by fulllines in Figs. l, 3

and 5. The arrangement of the torsion spring 28 and lugs Sii and 31 is fullyl explained in my prior Reissue Patent 24,426, reference being had thereto.

The latch element 23 is formed to provide a handle member 32 by means of which the latch element 23 may be rotated about its axis normal to the plane of the door 2 and between its above mentioned intermediate latching position, shown in full lines in Figs. 1 and 5,

and latch release position shown by dotted lines in Figs. 1 and 5. The latch element 23, Iadjacent the neck portion 22, is also formed to provide a circumferentially extended flange 33 which engages the boss 26 to limit axially inward movement of the latch element 23. The flange 33 is provided with a notch 34 that is aligned with a vertically extended slot 35 in the mounting plate 6 when the latch element 23 is in its above-mentioned latching position. A locking plate 36 is vertically slidably mounted in the mounting plate 6 and is provided with an angularly disposed locking tongue 37 that projects outwardly through the slot 35 for reception in the notch 34 upon downward movement of the plate 36, to releasably lock the latch element 23 against rotary movement away from its latching position. The locking plate 36 is provided with a stem 3S which extends outwardly through a slot 39 in the mounting plate 6, the stem '38 being provided with a knob 40, `by means of which the locking plate 36 is moved toward and away from locking engagement of the tongue 37 with the notch 34 in the flange 33. A spring pressed washer 41 surrounds the stern 38 inwardly of the knob 40, and is adapted to ride over detent means 42 to releasably hold the locking plate 36 in its locked or unlocked positions.

The latch element 23 is formed to provide a strike engaging curved cam surface 43 and a latching surface 44 that is generally normal to the axis of rotation of the latch element 23. A strike in the nature of a vertically extended pin 45 is mounted in a housing 46 that is provided with a mounting iiange 47 by means of which the housing 46 is secured to the door casing 3 inwardly of the shoulder- 4 thereof. The flange 47 is provided with a pair of diagonally extending parallel slots 4S for the reception of mounting screws 49 that are screw threaded into the door casing 3. The housing 46 defines an enlarged intermediate notch 50 across which the strike pin 45 extends, the opposite ends of the pin 45 being engaged by coil compression springs 51 which yieldingly urge the strike pin 45 into the path of movement of the latch element 23. As indicated by dotted lines in Pigs. l and 5, the strike pin 45 is movable out of the path of travel of the latch element 23 against yielding bias of the springs 51. During closing movements of the door 2, the strike pin 45 is engaged by the cam surface 43 and moved thereby toward the door casing 3 until the cam surface 43 moves beyond the strike pin 45 just as the door closes. The springs 51 then move the strike pin 45 into engagement with the latching surface 44 of the latch element to positively hold the door 2 against opening movements.

The latch element 23 further defines a iiat surface portion 52 angularly disposed with respect to the latching surface 44, the plane of the surface 52 being parallel to the axis of rotation of the latch element 23 and parallel to the strike pin 45 when the latch element 23 is in its latching position shown by full lines in Figs. l and 5. The surface 52 cooperates with opposite side surface portions 53 of the latch element 23 to define rounded cam-acting corner portions 54 which selectively engage the strike pin 45 upon rot-ation of the latch element 23 in either direction away from its latching position, and moves the strike pin toward the door casing 3 and out of the path of travel of the latch element 23 to permit opening of the door 2.

From the above, it will be seen that, by utilizing a retractable strike, and by having the latch element 23 formed with the cam-acting portions 54 for moving the strike pin 45 out of the path of movement of the latch element, it is not necessary that the strike be recessed in the door casing when a door is provided having an extremely narrow stile, requiring the latch to be very closely disposed relative to the door casing when the door is closed. Further, my novel construction, by utilizing the cam surface 43 to impart retracting movements to the strike pin 45 upon closing movements of the door, enables the door to be closed without turning the latch element 23 out of its normal latching position, turning of the latch element 23 being required only when it is desired to open the door.

My invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the objectives set forth; and while I have shown and described a commercial embodiment of my latch mechanism, it will be understood that the same is capable of modification without departure from the spirit and scope of the invention, as defined in the claim.

What I claim is:

In a door latch mechanism, a latch element and a cooperating strike, means for mounting said latch element `to one side of a door and adjacent an edge of the door for common movements with the door and for rotation on an axis normal to the plane of the door between a latching position and a latch release position angularly disposed with respect to said latching position, yielding means biasing said latch element toward said latching position, means `for mounting said strike to' a door casing -for movements into and out of the path of travel of said latch clement, yielding means biasing said strike toward said path of travel, said strike extending in a direction normal to the axis of rotation of said latch element, said latch element defining a cam surface engaging said strike upon movement of said latch element in a door closing direction to move said strike out of the path of travel against bias of said last-mentioned yielding means, said latch element further defining a latching surface angularly disposed to said axis of rotation of the latch element and projecting in a direction generally radially therefrom for latching engagement with said strike when said cam surface moves beyond said strike coincidental with closing of said door, whereby to hold the door against opening movement, said latch element further defining a surface portion between said latching surface and the adjacent side of the door and angularly disposed with respect to said latching surface, said surface portion being disposed in a plane in closely spaced parallel relation to the axis of rotation of the latch elment and generally parallel to said strike when said latch element is in its door closed and latching positions, said latch element having a side surface `angularly disposed to said surface portion and cooperating therewith to define a second cam having a curved strike-engaging surface, said curved cam surface engaging said strike responsive to rotation of said latch element whereby to move the strike out of said path of travel of the latch element in a door opening direction, and a handle integrally formed with said latch element and extending therefrom in a direction generally normal to the axis of rotation of said latch element for imparting rotation to the latch element against bias of said first mentioned yielding means, said latching surface being moved circumferentially about the axis of rotation of said latch element during said rotation thereof and in a direction away from engagement with said strike.

References Cited in the file of this patent UNITED STATES PATENTS 276,333 Baldwin Apr. 24, 1883 2,183,085 Richardson Dec. 12, 1939 2,200,702 Oddie May 14, 1940 2,733,089 Grevengoed Jan. 3l, 1956 

